Optimisation of Structural Systems with Regards to Future Repurposiong Current Practices and Suggestions for Improved Design Methods

Abstract

As the climate situation becomes more critical, sustainable solutions and behavioural changes are required in all sectors and contexts. One sector that contributes significantly to greenhouse gas emissions is the building and construction sector. Therefore, it is necessary to start evaluating and rethinking how we can address the demand for new buildings in ways that are more environmentally sustainable and climate-smart compared to current methods. This involves assessing opportunities for repurposing, reuse, and refurbishment instead of demolishing and rebuilding. The purpose of this master’s thesis is to evaluate what influences the possibility of repurposing and how one can overcome these challenges in different ways. Is optimising for current purposes and later strengthening critical parts the best approach, or should one overdimension to enable future repurposing and increased flexibility? Four different case studies were conducted to evaluate the common consequences of repurposing. The case studies were carried out for two different systems: a steel system with HDF floor slabs and a timber system with CLT floor slabs. To evaluate various situations, the studies were conducted using parametric design, with background information based on a literature review and insights from industry experts. The results showed that there are good opportunities for strengthening measures in steel systems, making it a feasible alternative when choosing steel as a building material. It is recommended to optimise the use of materials in new constructions to apply suitable reinforcement methods during repurposing. The results also indicated that reinforcement methods for timber systems are somewhat more complicated, and there is not as much benefit in optimising current structures. Therefore, a combination of overdimensioning and subsequent reinforcement during potential repurposing is suggested. Finally, a conclusion is drawn regarding the importance of constructing buildings in a way that allows for future reinforcement. This is crucial in determining potential future reinforcement measures’ complexity, material and energy requirements.